I didn't mean to imply that my intelligence really dropped, just that 
I let my math and verbal skills grow rusty as I explored other modes 
of experience.
Lyle wrote:
<I could still write -- both prose and computer code -- but only with 
great effort.  My attention span wasn't what it had been ... I don't 
know of anybody whose test scores went *up* after taking acid. I'm not 
saying this never happens -- all drugs affect different people in 
different ways -- but I never heard of it happening.>
Perhaps the problem was that you needed to be analytical - writing 
prose and computer code - and the psychedlic mode of thinking was not 
conducive to that.
Looking back through my notebooks from that time period, I see that I 
wrote some rather long-winded poetry and drew up some interesting 
conceptual diagrams, but my essays look somewhat incoherent in 
retrospect.
<I didn't get my strength back until I was in my thirties. 
 Ironically, it was pot that helped me put myself back together.>
I had a very similar experience, though I never felt that I was a 
casualty of drug usage, it was mostly a lack of coherent purpose from 
too many nihilistic memes.  Finally going to college and being 
determined to take up a profession after initially rejecting all of 
that helped to straighten me out more than anything.
Mark
"[C] ircuits in the brain generate local electrical discharges 
[causing] a feeling of suspension in space and time ... The sense of 
infinity makes the self feel immortal, and the fear of extinction goes 
away." - Michael Persinger, in Dec88 OMNI, discussing why intoxication 
is a human need.